While pipe couplings have seals formed of an elastomeric material have been used with great success, the use thereof is encumbered with one problem which can occur under particularly adverse conditions. This problems arises in the event that a fire occurs in the immediate vicinity of the coupling of sufficient intensity to cause heating of the elastomeric seal, and eventually, thermal destruction of the elastomeric seal contained within the coupling.
Under particularly adverse conditions, the seal can reach temperatures sufficient to cause volatilisation, vaporisation and carburization of the elastomeric material to the point of total destruction of the seal, and, the conversion of the elastomeric material into a porous and friable coke-like material.
If such a circumstance occurs, then, sealing of the coupling is negated or impaired, with the consequence that fuel comprised by the fluid content of the pipeline assembly is added to the existing external fire, with probable aggravation of the fire condition. In the event that the pipeline assembly is employed for conveying water used for fire extinguishing apparatus, then, the water pressure is lost or severely reduced, thus impairing the efficiency of the fire fighting equipment associated with the pipeline. If the pipeline assembly is employed for conveying noxious substances such as acids or caustic solutions, then, extensive clean-up is required subsequent to the correction of the condition.